Improvement in gearings for valve-movements for steam-engines



W. S. BACON.

Improvement in Gearings for Valve Movementsfor Steam-Engines. N0. lPatented Oct. 15, 1872.

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UNITED STATES l PATENT OFFICE.

WILLIAM S. BACON, OF SULPHUR SPRINGS, OHIO.4

IMPROVEMENT IN GEARINGS FOR VALVE-MOVEMENTS FOR STEAM-ENGINES.

Specification forming part of Letters Patent No. 132,130, dated October15, 1872.

To all whom it may concern:

Beit known that I, WILLIAM BACON, of Sulphur Springs, in the county ofCrawford and State of Ohio, have invented certain Improvements inValve-Movement for 'Steam- Engines, of which the following is aspecification:

My invention relates to valve-gear of steam.- engines, and consists incertain modifications and improvements in the construction of the same,as hereinafter shown and described.

In the accompanying plate of drawing which illustrates my invention andforms a part of the specification thereof- Figure 1 is a plan view of myimproved valve-gear, and Fig. 2 is a side view of same.

In the drawing referred to, letter A designates the frame supporting theapparatus; B, the cylinder 5 (l, the steam-chest; D, the valveconnecting-rod; E E' designate the elliptical spur-gears; F, thecrank-wheel; G, the valve guide-rod; g, the valve-stem; and H, theengine-shaft. My improvements consist in so constructing and arrangingthe valve-gear as to produce a movement that steam can be usedexpansively with single valve. To effect this the valve must have avaried motion quite different from that obtained by the small crank oreccentric alone, as commonly used, which, when set-screwed or keyed,always remains stationary relative to the engine-crank, which conditionprevents the use of steam expansively without excessive compression ortoo early exhaust, or both; hence, a cut-off77 is frequently placed onthe back of the valve, moved by an additional eccentric, and consequentloss of power results. In my improvements it is proposed to so move thesingle valve by retarding and increasing its motion that the steam canbe cut off at any point of stroke desired, and yet keep the port open atpleted, when the motion of the valve will be i quickened and throw theother exhaust-port Wide open, suddenly relieving the engine of exhauststeam almost instantly, thereby reducing the neutrality of the valve toa minimum. The elliptical-toothed gears E E are employed to accomplishthis, and it will be observed, on examinatiomthat the varied motion isobtained as each toothed gear alternates from a large wheel to a pinion,twice in each revolution of engine. The application of this principle tosuch purpose is also intended to save, to some extent, the power thatdrives the lower or under valve-that is, when a cut-off, is usedand inaddition. to the gain of expansion to gain further by relieving theengine of exhaust steam much quicker than can be done with the ordinaryeccentric unless greater movement is given, when, of course, greaterfriction will be incurred. By lengthening or shortening the crank on thesmall` shaft the valve is practically shortened or lengthened, and thusadapted to cut off at the desired point.

I claim, in a device for valve-movement for steam-engines- Theelliptical spur-gears in combination with the valve, connecting-rod,guide-rod, steamchest, and crank-wheel, all being constructed andoperating substantially as set forth.

In testimony of this my application for Letters Patent of the Uni tedStates for an improvement in valve-movement for steam-engines I hereuntosubscribe my name the day and year first above written.-

' `WILLIAM S. BAGON.

Witnesses:

J. H. FRY, Jr., I. W. ABERNETHY.

